Charlie Johnson, 40, who was arrested at his home by Oakland police on Friday, was scheduled to be arraigned on an assault charge in Alameda County Superior Court in Hayward Tuesday afternoon, authorities said.

San Leandro police haven’t disclosed a motive for the attack at the store, which is located at 555 Bancroft Ave., at about 10:55 a.m. on Sept. 23.

The suspect entered the store, approached the manager and suddenly punched him, knocking him to the ground and then fleeing, police said.

San Leandro police spokesman Lt. Randall Brandt said the manager, who is in his early 50s, is still in “very serious” condition at a local hospital.

Brandt said Johnson wouldn’t have been identified without tips police received from video surveillance of the incident that was aired by local television stations the day after the incident.

He said the best information came from a law enforcement officer from another agency who recognized Johnson.

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